Second Hand Pro Trainer 5 1/2" 

"Three-piece sweet iron mouth with copper ribs and rollers. Designed to offer refined control and communication between rider and horse. It typically features a mild mouthpiece combined with short shanks or a gag action, allowing for increased leverage and responsiveness without being overly harsh. This bit is often used in training to encourage softness, correct head carriage, and improve lateral flexion. It's suitable for more advanced riders looking to fine-tune performance, especially in disciplines where quick, precise cues are important. Often used during western riding."